Backflow preventer-vacuum breaker



- June 15,1965 CALL J 3,189,037

BACKFLOW PREVENTER VACUUM BREAKER Filed Feb. 7, 1963 2 Sheets-Sheet 1 INVENTOR M00sr0 CALLEJO June 1955 M. CALLEJO 3 95 BACKFLOW PBEVENTER VACUUM BREAKER Filed Feb. 7, 1965 2 Sheets-Sheet 2 INVENTOR MooEsro CALLEJO United States Patent 3,189,037 BACKFLOW PREVENTER-VACUUM BREAKER Modesto Callejo, 167 Cuba Hill Road, Huntington, NY.

' Filed Feb. 7, 1963, Ser. No. 258,110

r 2 Claims. (Cl. 137-218) The present application is a continuation-in-part application of my patent application Serial No. 43,197, filed July 15, 1960, and now abandoned, which relates to an improvement over the back-flow preventer-vacuurn breaker disclosed by my Patent No. 2,512,479, dated June 20, 1950. c

The present invention relates to improvements in sanitary water protection devices and, more specifically, to a new and improved backflow preventer and vacuum breaker, in which the valve parts and arrangements provide a better hydraulic performance in the way of increased flow capacity .and lower friction l-oss,and which greatly facilitates and simplifies the field servicing of the device. 7

One object of the present invention is the provision of a device of the character described'which has an improved valve seat structure and an improved arrangement of the fluid passages. L

Another object of the present invention is the provision of a device of the character described which has an improved valve seat arrangement and an improved valve guide, and the structure of which permits a ready and easy assembly of parts.

A further object of the present invention is the provision of novel cooperating valve parts, which will prevent any possible failure of operation caused by foreign particles such as pipe chips.

A still further object of the present invention is the provision in a backflow preventer vacuurn breaker of a novel air inlet seat ring made of heat-resistant thermoplastic or other suitable non-v-ulcanizing material, which will insure reliable operation of the device during the application of fluid at elevated temperatures.

- With the foregoing and other objects which will appear as the description proceeds, the invention consists of certain novel details of construction and combinations of parts hereinafter more fully described and pointed out in the claims, it being understood that changes may be made in the construction and arrangements of parts of the embodiments disclosed without departing from the spirit of the invention .as claimed.

In the accompanying drawings I haveset forth two illustrative embodiments of my invention.

In said drawing:

FIGURE 1 is a vertical sectional view' of an illustrative example 'of an assembled backflow preventer-vacuurn breaker involving my invention;

FIG. 2 is a fragmentary partial section, similar to FIG. 1, showing the pants of the backflow preventervacuum breaker in another stage of operation;

FIG. 3 is a sectional view on the line 33 of FIG. 1;

FIG. 4 is an exploded view, partially in section, of the upper and interior parts of the backflow prevente-rvacuum breaker;

FIG. 5 is a detail plan view of one of the parts of the backflow preventervacuum breaker;

- Similar reference characters refer to similar parts throughout the several views.

Referring to FIGS. 1 to 5 of the drawing, the embodiment of the invention shown in these figures comprises a two-pant casing composed of parts 32 and 39. The part 32 is referred to herein as a body, which is provided with a fluid inlet opening 34 and a fluid outlet opening 36. The openings 34 and 36 are provided with convenient means such, for example, as screw threads to provide pipe connect-ions. The opening 34 is to be placed in communication with a water supply pipe or other fluid source. The opening 36 is available for connection to a fixture or appliance of any character.

The part 39, referred toher-ein' as a head, has an upstanding portion 41 which provides for atmospheric communication in the manner referred to hereinafter. The portion 41 is provided with a threaded opening 42 to receive a plug (not shown) or a conduit 16 shown in broken outline. When employed, the conduit 16 is open ended and provides for drainage ofany spurted fluid to a convenient location. The sporting effect, when encountered, is usually caused by water hammer surges in the piping connected to the b'ackflow preventer-'vacuum breaker.

The lower end of the head 39 has a circular enlargemeat 40 to engage a body gasket 12 when the screw threads 43 are engaged with cooperating threads in the body 32 for coup-ling the body 32 to the head 39. Th gasket 12 rests in a seat provided vby the rim 46. The upper end of the head 39 is provided with'an air inlet opening 78, which appears in FIG. 1 of the drawing. This, in effect, corresponds to the pipe 23 shown in the above referred to Patent No. 2,512,479. The conduit 16 corresponds to the above referred to pipe 23 of this patent, but is, or may be, used only in special circumstances, as stated. A dust cap 18 surmount-s the structure.

A feature of the present invention is illustrated as an air inlet seat ring 10, which is made of heat-resistant thermoplastic or other applicable non-vulcanizing material. A linear polyethylene and polypropylene, such as Nylon, for example, is suitable. p

A two-part valve mechanism composed of a plunger 14 and a piston 48 is guided by a valve guide 11. The latter is shown in detail in FIG. 5 of the drawings, and its configuration is also a feature of the present invention. The ring 10 is flanged as indicated at 52, so that the screw threads 49 adjacent the top of the valve guide serve to clamp the ring 10 in place against the gasket or washer 1'2 in cooperation with the threads in the short bore 51 in the head 3-9.

The plunger 14 is provided with a circular groove which receives a plunger ring 13. This plunger ring 13 is resilient and can admit a foreign body, suchas a pipe chip, to provide sufficient closure to prevent backsiphonage, even though the foreign body may be pinned at the seat 15. The plunger ring .13 is made of a suitable semi-soft heat-resistant material. causes the plunger to be lighter in weight, and the flanges flanking the groove 14a provide a suflicient guiding effect in the valve guide 11. The top flange is slightly larger for a purpose to be described hereinafter.

A washer or valve member 68 is seated on the piston 48. This washer 68, which comes into intimate contact with the rounded edge of the seat ring 10, is preferably composed of a material which is resilient and resistant to changing temperatures. [For example, resilient materials are known and available which retain their property of resiliency without becoming adhesive in any way and which do not flow to any appreciable extent at these temperatures. A flange 69 projects beyond the seat for the washer 68 so as to protect its edge. The washer 68 is retained in position by a metallic washer 72 and a nut 73, which is received on a projecting threaded stem 74 a of the piston 48. The offset or shoulder 4 facilitates as- A reduced portion or groove 14a problem of lining up the parts accurately to accomplish assembly. The described novel structure solves this problem.

The embodiment of my present invention described above greatly facilitate the exchange of the seal ring or the accessibility of the interior of the device, by making it comparatively easy to unscrew the head from the body, and then to exchange the seal ring or to do any other work required on the interior of the device, without removing the same from the pipes on which it is mounted.

In operation of the backflow preventer-vacuum lbreaker, embodying fe atures disclosed herein, under flow conditions, as the fluid is turned on at a supply valve (not shown) the piston rises immediately, sealing the atmospheric communication under pressure to prevent fluid leakage. The plunger rises next to form the flow outlet permitting the fluid to enter through the inlet, whence it flows up and around the plunger and out through the outlet. The piston and plunger are then in the up or operating position.

Under backflow or unbalanced pressure conditions the plunger instantly drops to the lower seat, sealing the water inlet and acting as a check against baclcflow from the outlet piping. The piston drops at the same time, admitting air and breaking the effect of the vacuum.

Since certain changes may be made in the above article and different embodiments of the invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which as a matter of language might be said to fall therebetween.

Having thus fully described my said invention, what I claim and desire to secure by Letters Patent in-the United States is:

1. A device of the character described comprising a housing having an inlet opening and an outlet opening right angularly disposed to the inlet opening and having an internally threaded open tubular portion opposite said inlet opening, a hollow head member having a vent opening and an outlet opening in its upper portion as well as an internally and externally threaded lower portion screwed into the tubular open portion of said housing, a cylindrical guide member extended into said housing having an annular externally threaded upper portion screwed into the lower portion of said head member and engaging the internal thread thereof and having also a perforated main portion provided with inwardly extending shoulder sections above its lower extremity, a free-moving gravityactuated plunger slidably mounted in said guide member being adapted to be reciprocated therein and having an increased upper portion engaging the interior of said guide member above the shoulder sections of the same, first seal means removably interposed between said head member and the upper portion of said guide member and extended into said guide member, second seal rneans mounted on a lower portion of said plunger and adapted for closing temporarily said inlet opening of said housing, and a piston slidably mounted on said plunger and adapted for engaging said first seal means for separating the interior of said head member from the interior of said housing.

2. A lba'clcflow preventervacuum breaker comprising a housing having an inlet opening in its lower portion and a lateral outlet as well as an open tubular top portion provided with an internal thread, a cap member having a vent opening and a lateral outlet as well as an internally and externally threaded lower extremity engaging the threaded extremity of the top portion of said housing and being upwardly extended therefrom, a cylindrical guide having an externally threaded upper portion and a perforated main portion a lower section of which is formed as an internal shoulder section and being screwed into the internal thread of said cap member and extended into said housing, a first annular seal having an upper portion interposed between said cap member and the upper portion of said guide and being extended thereinto, a gravityactuated hollow plunger slidable in said guide having an increased upper portion engaging said guide above the internal shoulder section thereof and having also a lower portion provided with an annular groove opposite the inlet opening of said housing, a second annular seal in the groove of said plunger being adapted for sealing engagement with an internal section of the housing surrounding the inlet opening thereof, a piston slidably mounted in said hollow plunger having a flat head portion, and

a sealing washer secured to the head portion of said piston being adapted for sealing engagement with said first annular seal when the piston is in its uppermost position. 7

References Cited by the Examiner UNITED STATES PATENTS ISADOR WEIL, Primary Examiner. 

1. A DEVICE OF THE CHARACTER DESCRIBED COMPRISING A HOUSING HAVING AN INLET OPENING AND AN OUTLET OPENING RIGHT ANGULARLY DISPOSED TO THE INLET OPENING AND HAVING AN INTERNALLY THREADED OPEN TUBULAR PORTION OPPOSITE SAID INLET OPENING, A HOLLOW HEAD MEMBER HAVING A VENT OPENIN AND AN OUTLET OPENING IN ITS UPPER PORTION AS WELL AS AN INTERNALLY AND EXTERNALLY THREADED LOWER PORTION SCREWED INTO THE TUBULAR OPEN PORTION OF SAID HOUSING, A CYLINDRICAL GUIDE MEMBER EXTENDED INTO SAID HOUSING HAVING AN ANNULAR EXTERNALLY THREADED UPPER PORTION SCREWED INTO THE LOWER PORTION OF SAID HEAD MEMBER AND ENGAGING THE INTERNAL THREAD THEREOF AND HAVING ALSO A PREFORATED MAIN PORTION PROVIDED WITH INWARDLY EXTENDING SHOULDER SECTIONS ABOVE ITS LOWER EXTREMITY, A FREE-MOVING GRAVITYACTUATED PLUNGER SLIDABLY MOUNTED IN SAID GUIDE MEMBER BEING ADAPTED TO BE RECIPROCATED THEREIN AND HAVING AN INCREASED UPPER PORTION ENGAGING THE INTERIOR OF SAID GUIDE 